JP2021173854A - Display device for vehicle - Google Patents

Abstract

To provide a display device for a vehicle capable of displaying each of a plurality of images suitably, as well as, realizing downsizing of an image display part.SOLUTION: A display device for vehicles comprises: an image display par 2 that includes a plurality of pixels 24 for displaying an image on an image display surface 23. The device projects an image light of the displayed image to a windshield of a vehicle by an optical system (3) so as to enable a virtual image of the image to be visible with a light reflected at a windshield (WS). The image display part 2 includes a prism sheet 22 disposed on the image display surface 23. The prism sheet 22 includes a plurality of microprisms 26 arranged respectively facing the plurality of pixels 24 constituting one image, and individually deflecting the image light emitted from the pixels 24, respectively.SELECTED DRAWING: Figure 3

Description

The present invention relates to a display device mounted on a vehicle such as an automobile, and particularly to a head-up display device (hereinafter, HUD device).

As a HUD device, a device has been proposed in which light that constitutes an image is projected onto the windshield of an automobile so that a occupant such as a driver can visually recognize a virtual image of the image by the reflected light. In the following, making a virtual image visible is also referred to as displaying an image. In addition, a HUD device capable of displaying a plurality of images with one HUD device has also been proposed. For example, in Patent Document 1, light of a plurality of images (hereinafter, image light) displayed on an image display unit including a liquid crystal display (hereinafter, liquid crystal device) is emitted by an optical element in different directions. , A HUD device having a configuration in which each image is displayed independently has been proposed.

That is, the technique of Patent Document 1 is to display an image display unit by disposing an optical element made of a light guide on the display surface of the image display unit and inclining an exit surface that emits image light from the optical element. It refracts the image light emitted from the surface. Then, each image is displayed by making the angle of refraction, that is, the direction of refraction, different for each of the plurality of image lights.

JP-A-2018-173589

In the technique of Patent Document 1, the exit surface of the light guide body constituting the optical element is formed as one continuous inclined surface corresponding to the image. Therefore, when a plurality of images are displayed using such an optical element, each displayed image can be tilted and shifted in the depth direction. However, at the boundary of the prism that produces a plurality of image lights, the image light space that extends from the image display unit becomes uncontrollable light, and a problem that deteriorates the quality of the virtual image is likely to occur.

The above-mentioned defect is particularly likely to occur when the displayed images are close to each other. However, if an attempt is made to increase the distance between a plurality of images to be displayed, a large image display unit is required, which not only leads to an increase in cost but also increases the angle at which the image light is deflected. The angle of inclination of the surface also increases. Therefore, the dimension of the optical element in the optical axis direction becomes large, the thickness dimension of the optical element becomes large, and the thickness dimension of the image display unit provided with the optical element also becomes large.

An object of the present invention is to provide a vehicle display device that displays a plurality of images without being tilted and realizes miniaturization by forming an image display unit in a thin shape.

The present invention includes an image display unit including a plurality of pixels for displaying an image on an image display surface, and an optical system that projects the image light of the displayed image onto the windshield of the vehicle, and is reflected by the windshield. It is a display device for vehicles that makes it possible to visually recognize a virtual image of an image by means of light. The image display unit includes a prism sheet arranged on the image display surface, and the prism sheet is arranged to face a plurality of pixels constituting one image, and the image light emitted from the pixels is individually arranged. It is equipped with multiple microprisms that deflect to.

In the present invention, the optical system includes a concave mirror that reflects the image light emitted from the image display unit toward the windshield. Further, the image display unit can display a plurality of images on the image display surface, and the microprism has a configuration in which the image light is deflected at the same angle for the same image and different angles for different images. It is said that. Preferably, each microprism in the same image area deflects the image light at a certain angle, and the microprisms in an image area different from this image area are different from a certain same angle but the same in the image area. The configuration is such that it is deflected by an angle.

As a preferred embodiment of the present invention, a plurality of pixels on the image display surface are arranged in a matrix, and the plurality of microprisms are arranged in a single row pixel unit or a plurality of row pixel units facing each other. Alternatively, the pixels on the image display surface are composed of a plurality of sub-pixels, and the microprisms are arranged to face each other in units of sub-pixels. Further, the deflection angle of the microprisms arranged in a region away from the optical axis of the optical system is configured to be larger than the deflection angle of the microprisms arranged in a region close to the optical axis.

In the present invention, it is preferable that a plurality of microprisms are integrally formed on the same prism sheet. Further, it is preferable that the microprism is provided with an optical layer that diverges or diffuses light on an exit surface that emits image light.

According to the present invention, the direction of the image light projected on the windshield is configured to individually deflect the image light emitted from a plurality of pixels by the microprisms of the prism sheet arranged on the image display surface. Can be controlled and the image to be displayed can be controlled. As a result, a vehicle display device that displays a plurality of images in a suitable state and realizes a miniaturized image display unit is provided.

Conceptual configuration diagram of the HUD device. The schematic view of the HUD device seen from the side. An exploded perspective view of the schematic configuration of the image display unit. A cross-sectional view of a schematic configuration of an image display unit. A schematic plan view illustrating a form of image display. FIG. 3 is a cross-sectional view of a schematic configuration of a modified example 1 of an image display unit. FIG. 3 is a cross-sectional view of a schematic configuration of a modified example 2 of an image display unit. FIG. 3 is a cross-sectional view of a schematic configuration of a modified example 3 of an image display unit. FIG. 3 is a cross-sectional view of a schematic configuration of a second embodiment of an image display unit. The schematic optical path diagram explaining the operation of Embodiment 2.

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a conceptual configuration diagram of a HUD device applied to an automobile. The HUD device 1 is arranged in the dashboard DB of the automobile, and the image light L emitted from the HUD device 1 is projected onto the windshield (referred to as a windshield) WS of the automobile through the upper surface opening Ho of the dashboard. Let me. The projected image light L is reflected by the windshield WS and directed to the occupant M such as the driver of the automobile. When the image light L enters the eyes of the occupant M, the occupant M can visually recognize the virtual image I by the image light at the front position of the automobile through the windshield WS, and the image is displayed.

The HUD device 1 includes an image display unit 2 and an optical system 3 that projects an image displayed on the image display unit 2 onto the windshield WS. The image display unit 2 is capable of displaying a plurality of images, here two images. Further, the optical system 3 projects the image lights of the two images displayed on the image display unit 2 onto the windshield WS at different angles. As a result, the plurality of image lights L reflected by the windshield enter the eyes of the occupant M, and the occupant M can visually recognize the plurality of virtual images Ia and Ib.

That is, the image lights La and Lb of the two independent images displayed on the image display unit 2 are projected onto the windshield WS by the optical paths arranged in the horizontal direction, respectively, and these image lights La and Lb are the optical systems. The convex mirror 31 and the concave mirror 32 of No. 3 and the windshield WS are reflected in various influences, and by entering the eyes of the occupant M, the positions and inclinations of the virtual images Ia and Ib of each image can be visually recognized in a desired state. It is configured as follows. In this example, the virtual image Ia of the speedometer can be visually recognized on the left side through the windshield WS, and the virtual image Ib of the navigation can be visually recognized at a position behind the virtual image Ia on the right side.

FIG. 2 shows a schematic view of the HUD device 1 as viewed from the side surface direction. The optical system 3 further reflects the first reflecting unit 31 that reflects the image light L of the image displayed by the image display unit 2 and the light reflected by the first reflecting unit 31 and projects it onto the windshield WS. A second reflecting unit 32 is provided. The first reflecting unit 31 is composed of a convex mirror, and the second reflecting unit 32 is composed of a concave mirror. Here, the convex mirror 31 is composed of two convex mirrors 31a and 31b having different radius of curvature of the reflecting surface, the image light La is reflected by the convex mirror 31a having a predetermined radius of curvature, and the image light Lb has a larger radius of curvature than that. It is reflected by the convex mirror 31b. Further, even if the convex mirror 31a and the convex mirror 31b have the same curvature, the virtual image Ib is displayed at a position deeper than the virtual image Ia by arranging the convex mirror 31a at a position closer to the image display unit 2 than the convex mirror 31b. May be good.

The concave mirror 32 is composed of a spherical surface, an aspherical surface, or a free curved surface having a curvature that is a required focal length, and the convex mirror 31 improves the aberration in the concave mirror 32 and substantially extends the focal length of the concave mirror 32. .. Then, by configuring the HUD device 1 so that the image displayed on the image display unit 2 is arranged within the focal length of the concave mirror 32, the occupant M can visually recognize the virtual image I of the displayed image.

(Embodiment 1)
FIG. 3 is an exploded perspective view showing a schematic configuration of the image display unit 2 of the first embodiment, and the image display unit 2 includes a liquid crystal device 21 and a prism sheet 22. The liquid crystal device 21 can display a desired image on the image display surface 23, and an existing one can be used. Further, although the liquid crystal display 21 is shown in a simplified diagram in FIG. 3, the liquid crystal display surface 23 is composed of a large number of pixels 24 in which the image display surface 23 is matrix-arranged in the matrix direction. The image display surface 23 is divided into two regions in the row direction, the A image Oa is displayed in one A region 23a, and the B image Ob is displayed in the other B region 23b. Here, the A image Oa corresponds to the speedometer image, and the B image Ob corresponds to the navigation image.

Further, the liquid crystal device 21 is configured as a color liquid crystal device in which each pixel 24 includes three sub-pixels (sub-pixels) 25 (25r, 25g, 25b) of RGB, so that a color image can be displayed. ing. These sub-pixels 25 are arranged side by side in the row direction. Further, the plurality of pixels 24 arranged side by side in the column direction have the same arrangement as each of the RGB sub-pixels 25 (25r, 25g, 25b). The actual pixel 24 has an extremely small size, and the A image Oa and the B image Ob are displayed by the minute pixel 24. However, in FIG. 3, a large size is used to explain the correspondence with the prism sheet 22. It is illustrated in.

The prism sheet 22 is a material having a translucent property and a refractive index, and is composed of a sheet made of a material having good transferability such as resin, although it is not limited, and has a large number of wedge shapes (triangular shapes). ) Are arranged and integrally formed on a plane. These microprisms 26 are composed of two types of A microprisms 26a and B microprisms 26b, each of which has an exit surface inclined in the row direction. These A microprisms 26a and B microprisms 26b are arranged corresponding to the pixels 24 of the liquid crystal device 21. Here, the pixels are arranged in a single row of the pixels 24 arranged in a matrix, which is a so-called reticular lens configuration. Further, each exit surface of the A microprism 26a and the B microprism 26b has the same inclination angle, but is configured as an inclined surface inclined in the direction opposite to the row direction in the inclination direction. The height dimension, that is, the thickness dimension is the same for each of the micro prisms 26a and 26b.

As shown in FIG. 4 showing the cross-sectional structure of the image display unit 2, the back surface of the prism sheet 22 is flat, and the back surface is in close contact with the image display surface 23 of the liquid crystal device 21 and has a predetermined positional relationship. It is attached. That is, the plurality of A microprisms 26a and B microprisms 26b are attached in a state of being positioned with respect to the pixels 24 in each row of the liquid crystal device 21. Therefore, the image light La emitted from the pixel group of the A region 21a is refracted by the A microprism 26a toward the outside (left direction in FIG. 4) with respect to the center and is emitted from the exit surface. The image light Lb emitted from the pixel group of the B region 21b is refracted by the B microprism 26b toward the outside (right direction in FIG. 4) with respect to the center and is emitted from the exit surface. However, when the distance increases from the microprisms of the image light La and the image light Lb toward the convex surface, only one of the image lights may face outward.

FIG. 5 is a schematic plan view for explaining a form of image display in the HUD device 1. When the A image and the B image are displayed on the image display unit 2, as shown in FIG. 4, the image light of the A image Oa (hereinafter referred to as the A image light) La is deflected to the left with respect to the optical axis by the A microprism 26a. Then, the image light (hereinafter, B image light) Lb of the B image Ob is deflected to the right with respect to the optical axis by the B microprism 26b. The optical path through which the light emitted vertically from the center of the liquid crystal display surface 23 passes is defined as the optical axis Lx.

The A image light La and the B image light Lb deflected in opposite directions are reflected by the convex mirrors 31a and 31b, then reflected by the concave mirror 32, and then projected onto the windshield WS. Therefore, when these image lights La and Lb are reflected by the windshield WS and enter the occupant's eyes, the occupant enters the A image Oa and the B image Ob, here each virtual image of the speed meter image and the navigation image, that is, the A virtual image. Ia and B virtual image Ib can be visually recognized, and each image is displayed. At this time, the B virtual image Ib is displayed at a position deeper than the A virtual image Ia.

Conventionally, when the image lights of the A image Oa and the B image Ob to be displayed are displayed on the image display surface 23 in a state of being close to each other in the image display unit 2 configured by the liquid crystal device 21, the A virtual images Ia and B are displayed. The virtual image Ib is also displayed in a close state, and both images may be separated and cannot be visually recognized. In the HUD device 1, since the prism sheet 22 is arranged on the image display surface 23 of the liquid crystal device 21, the prism sheet 22 deflects the image lights La and Lb of the images Oa and Ob to obtain a desired angle difference. Can be attached.

As a result, the A virtual image Ia and the B virtual image Ib can be visually recognized at a desired interval, and a preferable display becomes possible. This angle difference can be changed by adjusting the angle of the exit surface of the A microprism 26a and the B microprism 26b. Therefore, it can be configured to observe the A virtual image Ia and the B virtual image Ib in any direction when viewed from the occupant. For example, by making the angles of the exit surfaces of the A microprism 26a and the B microprism 26b different, the directions of the A virtual image Ia and the B virtual image Ib can be set individually.

Since the micro prism 26 is configured as one prism sheet 22, even if it is attached to the image display surface 23 of the liquid crystal device 21, the thickness dimension of the liquid crystal device 21, that is, the increase in the thickness dimension of the image display unit 2 is the prism sheet. Only the thickness dimension of 22 is available. Further, since one of the micro prisms 26 is formed corresponding to the pixels 24 in one row of the liquid crystal device 21, the dimensions in the row direction are extremely small. Therefore, even if the inclination angle of the exit surface of the microprisms 26 is increased in order to increase the deflection angle of the image light, the increase in the thickness dimension of each microprism 26 can be extremely small. As a result, the thickness dimension of the prism sheet 22 can be reduced, the thickness dimension of the image display unit 2 does not become significantly large, and a small HUD device is configured.

Further, since the microprism 26 composed of the A microprism 26a and the B microprism 26b can be manufactured as a prism sheet 22 by integral molding with a translucent resin or the like, the microprism 26 is manufactured to the dimensions of the pixels 24 to the sub-pixels 25. Is easy. Moreover, if the prism sheet 22 is positioned with respect to the liquid crystal device 21, the micro prism 26 can be accurately positioned with respect to the corresponding pixel 24, and from this point as well, the image display unit 2 can be easily manufactured.

(Modification example 1)
FIG. 6 is a cross-sectional view of a modified example 1 of the image display unit 2. The same reference numerals are given to the portions equivalent to those of the first embodiment. In this modification 1, one microprism 26c of the prism sheet 22 is arranged in units of two rows of pixels 24 of the liquid crystal device 21. That is, one microprism 26c is arranged to face the pixels 24 in the two rows, and one microprism 26c is configured to deflect the pixel light of the pixels 24 in the two rows facing each other.

Also in this modification 1, it is possible to visually recognize each virtual image of the A image and the B image at a required interval as in the first embodiment. Further, since the image light is deflected for each of the pixels 24 in the two rows, it is possible to suppress the inclination of the virtual image that is visually recognized as compared with the technique of Patent Document 1. Further, when the modification 1 is applied to a liquid crystal display of the same standard, the number of micro prisms 26c formed on the prism sheet 22 can be reduced, so that the prism sheet 22 can be easily manufactured. On the other hand, in this modification 1, as the inclination angle of the exit surface of the microprism 26c increases, the height dimension of the microprism 26c, that is, the thickness dimension of the prism sheet 22 also increases, so that the angle at which the image light is deflected is relative. Suitable for application to small HUD devices.

(Modification 2)
FIG. 7 is a cross-sectional view of a modification 2 of the image display unit 2. In this modification, the prism sheet 22 is formed with microprisms 26d corresponding to each of the three RGB sub-pixels 25 (25r, 25g, 25b) constituting one pixel 24 of the liquid crystal device 21. That is, in one pixel 24, the image light of the three sub-pixels 25r, 25g, and 25b is independently deflected by the microprism 26d.

Also in this modification 2, it is possible to observe the virtual images of the A image and the B image at desired intervals. Further, since the image light is deflected for each sub-pixel, the inclination of the visually recognized virtual image can be suppressed. Further, in the second modification, the row direction dimension of the microprism 26d can be shortened corresponding to the dimension of the sub-pixel 25, so that even if the inclination angle of the exit surface is increased, the height dimension of the microprism 26d, that is, It is possible to suppress an increase in the thickness dimension of the prism sheet 22. Therefore, even if it is applied to a HUD device that requires a larger interval dimension between the virtual images of the A image and the B image, it is possible to prevent an increase in the thickness dimension of the image display unit 2.

(Modification example 3)
FIG. 8 is a cross-sectional view of a modified example 3 of the image display unit. In the third modification, an optical layer 27 that diverges or diffuses the emitted image light is laminated on the exit surfaces of the A microprism 26a and the B microprism 26b of the first embodiment. Alternatively, the optical layer 27 may be configured as a concave lens microprism that radiates light.

In the third modification, the light flux (bundle of light) of the image light emitted from the microprisms 26a and 26b is expanded in the optical layer 27. Therefore, even if the image light is emitted from only a part of the RGB sub-pixels 25 in each pixel 24, it is almost the same as the case where the image light is emitted from one pixel 24, that is, the three sub-pixels 25r, 25g, 25b. A light beam is obtained, and a virtual image having uniform brightness can be visually recognized.

(Modification example 4)
Although not shown, as a modification 4, one microprism may be arranged for each pixel of the pixels arranged in a matrix as long as the prism sheet can be finely processed or manufactured. Alternatively, one microprism may be arranged for every sub-pixel. On the contrary, when the fine processing and manufacturing of the prism sheet are strict, one microprism may be arranged for each pixel in which a plurality of prism sheets are grouped in the row direction and / or the column direction.

(Modification 5)
Further, although not shown, as a modification 5, the microprisms may be arranged so as to face only a part of all the pixels constituting the image display surface. In this case, the image light of the other pixels is emitted in the vertical direction of the image display surface without being deflected.

(Modification 6)
Further, although not shown, as a modification 6, the liquid crystal device is configured to display three different images on the image display surface, and the prism sheet has A micro prism, B micro prism, and C micro having different inclination angles. Like the prism, it may be composed of three different micro prisms. For example, the A microprism deflects the A image light to the left, the B microprism deflects the B image light to the right, and the C microprism does not deflect the C image light. By doing so, three different images can be displayed side by side in the horizontal direction. It may be configured to display four or more images.

(Embodiment 2)
By the way, in the HUD device using the liquid crystal device 21 as in the present invention, the image light emitted from the image display surface 23 of the liquid crystal device 21 is emitted from the image display surface 23 as a substantially parallel light flux in the substantially vertical direction. Is required. Therefore, the contrast in the displayed image may be lowered. That is, as a characteristic of the liquid crystal device 21, when light is obliquely incident on the liquid crystal device 21, the positional relationship of the elements in the liquid crystal device 21 deviates from the suitable relationship, so that the light is substantially shielded or the light is substantially transmitted. Sometimes light leakage occurs. When this light leakage occurs, the brightness ratio of white and black that can be displayed by the liquid crystal device, that is, the contrast is lowered.

In the HUD device 1 of the first embodiment, the light emitted from the image display unit 2 is deflected in the same direction as long as it is in the same display area, but in the HUD device that displays a small and large virtual image, the image display surface. At the center of 23, the image light is vertical, and at the end, the image light is an image light that spreads outward with respect to the optical axis Lx. Therefore, at the end portion, a virtual image is displayed by light traveling obliquely through the liquid crystal display, and the contrast is lowered due to the above-mentioned liquid crystal characteristics.

In the second embodiment, as shown schematically in FIG. 10, the optical path of the light emitted from the liquid crystal device 21 is the image display surface 23 when the center of the image display surface 23 of the liquid crystal device 21 is set to the optical axis Lx. At the center of, the image light Lc is vertical. The contrast is improved by controlling the deflection of the image light Ls emitted from the region away from the optical axis Lx, that is, the peripheral region away from the center of the image display surface 23. That is, with respect to the microprisms formed on the prism sheet, the inclination angle of the exit surface of the microprism corresponding to the peripheral region of the image display surface 23 is relative to the inclination angle of the exit surface of the microprism on the center side thereof. It is enlarged to.

FIG. 9A is a cross-sectional view of a first example of the image display unit 2 of the second embodiment. In this first example, one microprism 26 is arranged for one row of pixels 24 of the liquid crystal device as in the first embodiment, but the microprism 26d in a region close to the optical axis of the image display surface 23 The inclination angle of the emission surface of the region microprism 26e away from the optical axis is made larger than the inclination angle of the emission surface of the above. By doing so, the deflection angle of the image light emitted from the microprism 26e in a distant region becomes large, but since the light traveling in the liquid crystal display in a nearly vertical state is used, the contrast is lowered. It can provide a good quality display.

In the second embodiment, as shown in the cross-sectional view of FIG. 9B, the microprisms 26f corresponding to one pixel 24 are arranged in the region near the optical axis, and the sub-pixel 25 (in the region away from the optical axis). A microprism 26g corresponding to 25r, 25g, 25b) may be arranged. By doing so, the height dimension of the microprism 26g is increased as compared with the case where the inclination angle is increased as in the case of the microprism 26e arranged for one pixel shown in FIG. 9A. Can be prevented, and the thickness dimension of the prism sheet 22 can be prevented from increasing.

In the embodiments and modifications described above, an example in which a plurality of images are displayed side by side in the horizontal direction is shown, but the present invention can be similarly applied to a case where virtual images are displayed side by side in the vertical direction, that is, in the vertical direction. can. In this case, the image light may be deflected in the column direction by the microprism formed on the prism sheet.

In the present invention, since the image display unit may be configured to emit image light, an optical system using a DMD device in which fine mirrors are arranged in a matrix to selectively reflect the light of the light source and emit the image light. It may be configured as an intermediate image. Alternatively, it may be composed of an organic EL. Further, the first reflecting portion of the optical system is not limited to the convex mirror, and may be a plane mirror. Further, if the HUD device does not interfere with other devices of the automobile or the like, the optical member other than the concave mirror may be omitted. Further, at least one of the optical systems 3 may be divided into two or more, and each may be configured as a dedicated optical system for a plurality of images.

The windshield in the present invention is not limited to the windshield of the automobile described in the embodiment, and may be a part of a vehicle body such as a translucent window provided in the vehicle.

1 HUD device 2 Image display unit 3 Optical system 21 Liquid crystal device 22 Prism sheet 23 Image display surface 24 Pixel 25 (25r, 25g, 25b) Sub-pixel 26 (26a, 26b, 26c, 26d, 26e, 26f, 26g) Micro prism 27 Optical layer 31 (31a, 31b) First reflector (convex mirror)
32 Second reflector (concave mirror)
WS Windshield Oa, Ob Image I, Ia, Ib Virtual Image L, La, Lb Image Light Lx Optical Axis

Claims (10)

An image display unit having a plurality of pixels for displaying an image on an image display surface and an optical system for projecting the image light of the displayed image onto the windshield of the vehicle are provided, and the light reflected by the windshield A vehicle display device capable of visually recognizing a virtual image of an image, wherein the image display unit includes a prism sheet arranged on the image display surface, and the prism sheet constitutes a plurality of images. A display device for a vehicle, which is provided with a plurality of microprisms arranged to face each of the pixels of the above and individually deflecting image light emitted from the pixels. The vehicle display device according to claim 1, wherein the optical system includes a concave mirror that reflects the image light emitted from the image display unit toward the windshield. The image display unit can display a plurality of images on the image display surface, and each microprism in the same image area deflects the image light at a certain angle, and the image is different from the image area. The vehicle display device according to claim 2, wherein the microprisms in the region are deflected at the same angle in the image region while being different from the same angle. The vehicle display device according to claim 3, wherein the plurality of pixels on the image display surface are arranged in a matrix in a matrix, and the plurality of microprisms are arranged to face each other in units of one row of pixels or units of multiple rows of pixels. The vehicle display device according to claim 3, wherein the pixels are composed of a plurality of sub-pixels, and the microprisms are arranged to face each other in units of sub-pixels. The fifth aspect of the present invention, wherein the deflection angle of the microprisms arranged to face each other in one pixel unit is smaller than the deflection angle of the microprisms arranged to face one sub-pixel. Vehicle display device. The microprism is configured such that the deflection angle of the microprisms arranged in a region away from the optical axis of the optical system is larger than the deflection angle of the microprisms arranged in a region close to the optical axis. The vehicle display device according to any one of claims 1 to 6. The microprism has an inclined exit surface that refracts and emits the image light, and the inclination angle of the emission surface of the microprism having a large deflection angle is larger than the inclination angle of the emission surface of the microprism having a small deflection angle. The vehicle display device according to any one of claims 1 to 7. The vehicle display device according to any one of claims 1 to 8, wherein the plurality of micro prisms are integrally formed on the same prism sheet. The vehicle display device according to claim 8 or 9, wherein the microprism includes an optical layer that diverges or diffuses light on an exit surface that emits the image light.

Images